Conversion of high-boiling hydrocarbon oils into lower-boiling oils



P. SWEENY CONVERSION OF HIGH BOILING HYDROCARBON OILS INTO LOWER BOILING OILS Filed Jan. 11, l926 fffzi g/ J1.

atented tine 22 M26.

'rnrtttr It. ensures, or 'w'IIIrIn'e, Innmitn, nssreiton no s'rartnann on; COMPANY,

UT 'WITTTTNG; INDIANA, AND Cl-TTCAGU,

lllilhllllltllfl, A TtlPRATION Gi l INDIANA.

UQNVERSTON 0L HIGH-BOILING-HYJDRCEBN EELS HTTU LQtVlilR-BQTLTNG 011.4%.

Application filed January The present invention relates to improvements in the conversion of hydrocarbon oils of higher boiling points than gasoline into hydrocarbon oils of the gasoline range of U boiling points. lt will be fully understood from the following description illustrated by the accompanying drawing, in which ap- *atus for carrying the invention into elis diagrammatically illustrated par- .tt tially in elevation.

Referring more particularly to the drawings, the numeral indicates a suitable fur nace setting in which is mounted a heating coil 6, to which oil to be operated upon to is supplied through the inlet line 'l. The heated oil passes trom the coil 6 through the line 8 into a manifold 9. From the manifold 9 valved teed lines 10 ll 12 and 13 lead to the chambers ll, l5, l6 and 1? respectively. Each ot the chambers i l, 15, 16 and 17 is provided with a valve draw-oil line, these being numbered 155, 19, 20 and 21. These draw-0d lines lead to a common tar manilold 22, which leads, for example, to a tar heat exchanger and storage receptacle (not shown) or other suitable devices. The chambers 14, 15, 16 and 17 are intercom nected at approximately the level or liquid maintained therein by the pipes 2d; and 3@ their vapor spaces are interconnected by the pipes 25. A vapor line 26 leads from the vapor space ot one of the interconnected chambers for ex rnple, l7, to the lower portion of a dephlegmating tower 27. Vapors 35 heavier than the desired distillate product are condensed within the dephlegmator 27,

cooling action being aided by a suitable reflux cooling coil provided in the upper portion of the dephlegmator 27, the to coolir medium being supplied thereto through pipe 28 and, leaving the dephlegmator, somewhat preheated, through the Uncondensed vapors pass out of hlegmator 2? through the line 30 to le condenser ill, the condensate beng in the receptacle 32.

1. uch as oil oil a character suitable aged in the system is preferably the cooling medium in the upper or" the dephleginator, the line 29 is suite? extended to communicate with the inlet :ie I? of the heating coil 6. ltetlux con ensate "from the dephleginator 2? in lilio o preferably withdrawn by a line 33 part1 collected and separated from accom-' 1;, 1926. Serial No. 89,585.

and forced by a pump 34 through line 35 to the inlet 7 ot the heating coil 6.

The oil to be treated in accordance with this invention is supplied through the inlet '2 to the heating coil 6 in which it is brought to a conversion temperature above 700 F. and preferably in the neighborhood of 800 F. although temperatures as high as 950 to l000 may be employed. The pressure at the outlet of the coil and throughout the remainder or the system is maintained in excess of 60 pounds gauge and preferably at 200 pounds or higher. The oil is caused to flow through the heating coil at a rate of speed sutlicient to prevent any substantial deposition of coke therein.

From the coil ii the heated oil passes through the line 8 to the manifold 9. The supply of oil from the manifold to the enlarged chambers 14-, l5, l6 and 1.7 and the withdrawal of oil therefrom is so controlled that the oil flows in series through the enlarged chambers at a greatly reduced rate of speed, being maintained therein conversion temperatures whereby substantial conversion is effected therein. Tl desired mild heat may be supplied to the chambers so that no very substantial drop of temperature will talre place therein. Thus, the temperature of the oil within the chambers i l, 15, 16 and it? may be less than that at the outlet of the coil 6, or the differential may be even less than this. Thus, with a coil outlet temperature of 800 to 810F. the oil in the enlarged chambers may well be maintained at 780 to 790 The vapors from the intercommunicating vapor spaces of the chambers pass throu h the,

line 16 to the dephlegmator, as already fully set forth.

Tn the initial stages of operation, the oil may be passed, for example, from manifold 9 through line 10 into still ll, or through lines 10 ll into chambers ll and T5. Tar may be withdrawn continuously or intermittently from the chamber 17 or from chambers 16 and 1?. Thus it has been found satisfactory to withdraw substantially three fourths of the tar removed from the still l? through the line 21, the remaining one-fourth being drawn from the chamber 16 through. the line 20. litter the operation been conducted this manner for period of time sufidcient to cause a substantial formation ot coke and asphaltic matter in the the withdrawal of tar from the chambers 17 and 16 is discontinued, and tar is drawn from the chamber 14 through the line 18 ,or from the chambers 14 and 15 through the lines 18 and 19, for example, in the same manner as tar was previously withdrawn from the chambers 17 and 16. .As a result of the reversal of flow of the oil; it is found that there is a substantial'reduction in the coke and asphalt-i0 accumulations in the chambers 17 and 16, which were formerly at the end of the series, and coke and asphaltic accumulations apparently begin to build up in the stills 14 and 15, which are now at the end of the series. ,VVhen these accumulations become substantial, as indicated by the char acter and flow of the tar or by other indicia, the direction of flow is again reversed, flow being resumed as originally described. In this manner, the flow is reversed at intervals during the operation of the system, and the length of a run has thereby been substantially increased. Thus, runs up to and exceeding 700 hours in length have been made when operating in accordance with the present invention.

Although the invention has been described in connection with the reversal of flow through the enlarged chambers after appreciable accumulations of coke and asphaltic matter in certain thereof, it is readily apparent that such accumulations may be forestalled by an earlier reversal of flow in the manner above set forth, such substantial accumulations of coke and asphalticmatter being thereby prevented. Thus, in the early stages of the run, the direction of flow may be reversed every 36 or 48hours, the intervals between reversals being shortened at later stages in the run to, say 24 hours.

It is not intended that the details of apparatus illustrated nor of the process as above set itorth shalt be regarded as limitations upon the scope of the invention, except in so far as included in the accompanying claims.

1 claim:

1. In the method of producing low boiling hydrocarbon oils or the gasoline range of boiling points from higher boiling hydrocarbon oils, passing the higher boiling oil in continuous flow in a restricted stream through a heated zone in which it is brought to conversion temperature, then causing the heated oil to pass at aslower rate in succession through a plurality of enlarged chambers at conversion temperatures, while maintaining pressure upon the oil through out the system, whereby substantial conversion takes place therein, and at intervals reversing the flow of the oil through said enlarged chambers.

2. The method of producing low boiling pointhydrocarbon oils in the gasoline range of boiling point from higher boiling hydrocarbon oils which comprises passing the higher boiling oil in continuous flow in a restricted stream through a heating zone in which it is brought to conversion temperature, discharging the heated oil from said stream into one of a plurality of series connected enlarged chambers through which the oil is caused to flow at a slower rate while conversion temperature is maintained there in, pressure being maintained upon the system, withdrawing liquid products of conversion from another of said eniarged chambers remote from the one into which the oil is caused to flow from the heating zone continuing the flow of oil through the enlar 1 chambers until substantial coke and mphal'i depositions take place in the later ones of series of enlarged chambers, and then cha ing the flow of oil from the heating nor a chamber from which liquid products previously withdrawn and Withdra. liquid products of conversion from ch her into which oii was previously admi. from the heatin zone, thereby reversing flow of oii through the series of enla: e" chambers.

PERRY S 

